Physical and analytical modelling of permeability damage in bituminous coal caused by fines migration during water production

This study presents a systematic experimental methodology to investigate permeability damage caused by fines migration. The workflow starts with a thorough characterization of a bituminous coal sample by the XRD, SEM-EDX, petrographic, proximate and ultimate methods. Then, a single-phase water flow test is conducted on the coal sample whose surface is covered with Araldite resin to eliminate coal creep. The water permeability is monitored continuously and produced water samples are collected at regular intervals. The produced water samples are tested for conductivity, ionic concentration and fines concentration and sizes. Finally, the produced fines are separated from water using a membrane filter and the fines are examined using the SEM-EDX analysis. The theory of maximum retention function is used to investigate the fines release mechanism.